Review of the principles and management implications related to nitrogen in the soil-plant-water system.

Nitrogen is an essential element for plant growth and development and a key agricultural input-but in excess it can lead to a host of problems for human and ecological health. Across the globe, distribution of fertilizer nitrogen is very uneven, with some areas subject to nitrogen pollution and others suffering from reduced soil fertility, diminished crop production, and other consequences of inadequate supply. Agriculture and the Nitrogen Cycle provides a global assessment of the role of nitrogen fertilizer in the nitrogen cycle. The focus of the book is regional, emphasizing the need to maintain food and fiber production while minimizing environmental impacts where fertilizer is abundant, and the need to enhance fertilizer utilization in systems where nitrogen is limited. The book is derived from a workshop held by the Scientific Committee on Problems of the Environment (SCOPE) in Kampala, Uganda, that brought together the world's leading scientists to examine and discuss the nitrogen cycle and related problems. It contains an overview chapter that summarizes the group's findings, four chapters on cross-cutting issues, and thirteen background chapters. The book offers a unique synthesis and provides an up-to-date, broad perspective on the issues of nitrogen fertilizer in food production and the interaction of nitrogen and the environment.

Biological nitrogen fixation. Why, when an how to measure nitrogen fixation. Analysis of nitrogen. Nitrogen Balance Method. Nitrogen Difference method. Ureide (N solute) metode. N-isotopic methods. N-abundance method. N isotopic ditution method. prcaution whenquantifying N2 fixation associated with no-nodulatin plants (associative N2 fixation). Assays of nitrogenase activity.

North American Agroforestry Explore the many benefits of alternative land-use systems with this incisive resource Humanity has become a victim of its own success. While we’ve managed to meet the needs—to one extent or another—of a large portion of the human population, we’ve often done so by ignoring the health of the natural environment we rely on to sustain our planet. And by deteriorating the quality of our air, water, and land, we’ve put into motion consequences we’ll be dealing with for generations. In the newly revised Third Edition of North American Agroforestry, an expert team of researchers delivers an authoritative and insightful exploration of an alternative land-use system that exploits the positive interactions between trees and crops when they are grown together and bridges the gap between production agriculture and natural resource management. This latest edition includes new material on urban food forests, as well as the air and soil quality benefits of agroforestry, agroforestry’s relevance in the Mexican context, and agroforestry training and education. The book also offers: A thorough introduction to the development of agroforestry as an integrated land use management strategy Comprehensive explorations of agroforestry nomenclature, concepts, and practices, as well as an agroecological foundation for temperate agroforestry Practical discussions of tree-crop interactions in temperate agroforestry, including in systems such as windbreak practices, silvopasture practices, and alley cropping practices In-depth examinations of vegetative environmental buffers for air and water quality benefits, agroforestry for wildlife habitat, agroforestry at the landscape level, and the impact of agroforestry on soil health Perfect for environmental scientists, natural resource professionals and ecologists, North American Agroforestry will also earn a place in the libraries of students and scholars of agricultural sciences interested in the potential benefits of agroforestry.

Nitrogen is one of the most critical elements for all life forms. In agricultural systems it is essential for the production of crops for feed, food, and fiber. The ever-increasing world population requires increasing use of nitrogen in agriculture to supply human needs for dietary protein. Worldwide demand for nitrogen will increase as a direct response to increasing population. Nitrogen in the Environment provides a wholistic perspective and comprehensive treatment of nitrogen. The scope of this book is diverse covering a range of topics and issues related to furthering our understanding of nitrogen in the environment at farm and national levels. Issues of nitrogen from its effects on crops and human nutrition to nitrogen in ground water, watersheds, streams, rivers, and coastal marine environments are discussed to provide a broad view of the problem and support scientists, researchers, and engineers in formulating comprehensive solutions. - The only source which presents an international, wholistic perspective of the effects of nitrogen in the environment with worldwide mitigation practices - Provides details on how to improve the quality of the environment by analyzing the development of emerging technologies - Develops strategies to be used by soil scientists, agronomists, hydrologists, and geophysicists for broad scale improvement of nitrogen efficiency

Nitrogen is the most yield-restraining nutrient in crop production globally. Efficient nitrogen management is one of the most important factor for improving nitrogen use efficiency, field crops productivity and profitability. Efficient use of nitrogen for crop production is therefore very important for increasing grain yield, maximizing economic return and minimizing nitrous oxide (N2O) emission from the fields and nitrate (NO3) leaching to ground water. Integrated nitrogen management is a good strategy to improve plant growth, increase yield and yield components, grain quality and reduce environmental problems. Integrated nitrogen management (combined use of chemical + organic + bio-fertilizers) in field crop production is more resilient to climate change.

Nitrogen is the most important nutrient in agricultural practice because the availability of nitrogen from the soil is generally not enough to support crop yields. To maintain soil fertility, the application of organic matters and crop rotation have been practiced. Farmers can use convenient chemical nitrogen fertilizers to obtain high crop yields. However, the inappropriate use of nitrogen fertilizers causes environmental problems such as nitrate leaching, contamination in groundwater, and the emission of N2O gas. This book is divided into the following four sections: “Ecology and Environmental Aspects of Nitrogen in Agriculture”, “Nitrogen Fertilizers and Nitrogen Management in Agriculture”, “N Utilization and Metabolism in Crops”, “Plant-Microbe Interactions”.

Mineral Nitrogen in the Plant-Soil System provides integrated accounts of the transformations and fate of mineral nitrogen in the plant-soil system. This book emphasizes the understanding of various processes and the factors that affect these processes. It also focuses on the role of biological nitrogen fixation in nitrogen cycling in natural and agricultural systems. The book is divided into seven major chapters and each chapter is further subdivided into various subtopics. The first chapter introduces and outlines the origin, distribution, and cycling of nitrogen in natural and agricultural terrestrial ecosystems. Chapter 2 focuses on the processes of decomposition and mineralization-immobilization turnover. The processes of nitrification are discussed in detail in Chapter 3. The following four chapters discuss topics of retention and movement of nitrogen in soils; gaseous losses of nitrogen; uptake and assimilation of mineral nitrogen by plants; and lastly, the use of nitrogen in agronomic practice. The book will be invaluable to graduate students and researchers in the field of agriculture. This will also cater other parties interested, such as agronomists, soil scientists, plant physiologists, horticulturists, and foresters.

Origin and distribution of nitrogen in soil. Soil inorganic nitrogen. Organic nitrogen in soils. Ammonium fixation and other reactions involving a nonenzymatic immobilization of mineral nitrogen in soil. Mineralization and immobilization of nitrogen in the decomposition of plant and animal residues. Nitrification. Denitrification. Symbiotic nitrogen fixation. Environmental factors in the fixation of nitrogen by the legume. Nonsymbiotic nitrogen fixation. The plant's need for and use of nitrogen. Movement of nitrogen in soil. Evaluation of incoming and outgoing processes thar affect soil nitrogen.